In liquid crystal display devices used in smartphones, tablet computers, etc., there has been demand for narrower frames. Therefore, if circuits such as a gate driver are built in a display panel, the built-in circuits usually adopt a one-side drive/one-side power supply method.
In a transmissive liquid crystal display device, to prevent deterioration of a switching element and leak current, a light-shielding layer serving as a shield against light from a backlight is provided in some cases. It is known that, to prevent the light-shielding layer from becoming electrically floating, the light-shielding layer is electrically connected to a gate electrode of the switching element, for example.